Bridge



(No Model.) 3 Sheets-Sheet 1 I WLJ. HOLMAN.

BRIDGE." 110,290,054. v Patented-Dec.11, 1883.

(No Model.) r v a Sheets-Sheet. W. J-. HOLMAN. I

BRIDGE.

No. 290,054. I PatentedrDec. 11, 1883. I

or. W IZZfiw M/JJIOZWW,

/wog/g IINi'rEn STATES. P TENT OFFICE.

WILLIAM JENNINGS HOLMAN, OF FORT WAYNE, INDIANA, ASSIGNOR OF ONE-HALF TOMIOAJAH 0. WHITE, OF MINNEAPOLIS, MINNESOTA.

' BRIDGE.

SPECIFICATION forming part of Letters Patent No. 290,054, dated December11, 1883.

' Application filed May 3, 1883. (No model.)

To all whom it may concern.-

Be it known that I, VVILLIAM J. HOLMAN,

' a citizen of theUnited States, residing at Fort provide open oruncovered bridges in which .more effectual provision is made forpreventing the decay of materials, and in which the timbers are 'soframed, locked, tied, or secured together as to be less complicated,cheaper, and far more rigid and permanent, and will better Withstan dthe thrusts and tension-strains to which bridges are subjected than inthe ordinary methods of construction- The invention consists in thenovel construction and arrangement of parts hereinafter described andclaimed, and ill istrated .in the accompanying drawings, in which Figure1 is a side elevation of ,a sectionof a truss-bridge, consisting,essentially, of top and bottom chords, lower cross-beams for supportinga railroad-track or flooring, vertical posts, "andinclined braces. Fig.2 is an end elevation of the bridge shown inFig 1. Fig. 3 is a plan ortop view of a wagon-bridge, show ing the lower chords, longitudinal andtransverse floor-beams, posts, and manner of securing these partstogether, with a breast-wall of planks, an end view of which is shown inFig. 4. Fig. 4 is a side View of bridge and breast-wall of planks at endof bridge, supported by, though. separated from, the ends of projectingtimbers by small cast-iron bars or. blocks. Fig. 5 is an end view ofsame without the breast-wall of planks. Fig. 6 is a detail view of thebolt employed for fastening the bridge-timbers together. Fig. 7 is acrosssection of a modified form of angular timber.

I desire it to be understood that I do not restrict my invention to theparticular forms of bridges herein illustrated and specificallydescribed, because it will be apparent that the principle or spirit ofmy invention can be embraced or embodied in all forms of bridges inwhich wooden timbers,whether horizontal, inclined, or vertical, areemployed and hence it will only be necessary to add that the partomcross-timbers, O G, the packing-sticks D,

the vertical posts E, the inclined braces F F,

and upper chord packingblock, G. These parts are all composed of piecesor sticks of timbers cut generally square in form, but set or laid insuch a way that the sides thereof present angular or inclined surfacesthe angles or corners of which approximately coincide with horizontaland verical lines. The lower chords, A, are each formed of two or moretiers of three parallel timbers, between which longitudinally betweenthe cross-timbers O G. The vertical posts E are arranged in pairs,

and fit between the timbers of the chords and between the cross-timbersO G, adjoining said parts, and the two sections of main braces F aremadeio foot, respectively, on the upper and lower of the two tiers ofcross floor-beams framed about the lower end of posts, while the upperends of the two sections of said braces shoulder in notches just beneaththe lower of the upper chord-sticks, as is shown in Fig. 1-. The varioushorizontal timbers constituting the bottom of the bridge structure aresecured together by means of notches made in their contact or abuttingsurfaces or points where two timbers cross each other, these notchesbeing always on the under side, when one stick may be above theother, soas to leave no exposed crevices for lodgment of moisture. In otherwords, where two timbers cross each other the top corner apex of onetimber is received in a notch made in the nether or lower corner of theother timber.- For securing the parts joined in this manner. I make useof a bolt, M, which has a flanged head, N, that projects on all sidesfrom said bolt and has its interior face made inclined or shaped in sucha manner as to fit snugly on,

about, and around the angle or corner of the j block.

iron washer, O, which corresponds in shape to the head N, and is usedfor the samepurpose. The washer O is secured by an ordinary nut on thescrew-threaded end of the bolt. The posts are secured to the bottomchords in any preferred way. For example, the posts may be notched attheir lower ends for the reception of lower chord-sticks of the bottomchord, and the upper chord-sticks of said chords may be notched for thereception of the corners of the posts.

It will be understood that the bolts used for connecting the varioustimbers, whether the same be arranged horizontally, vertically, orobliquely, are always by their heads and washers made to conform to theplane or angular surfaces at the point of contact with the tint bersinto and through which the bolts are inserted. generally in conformationwith the one above described. Each top chord B is, in the constrlu-tionshown in Figs. 1 and 2, composed of three parallel timbers or sticksupon the same plane and an upper stick,which, together with the middlelower stick. are fitted between the double posts E, the other sticksfitting against the outer sides of said posts. A bolt. passes throughthe three lower sticks and the two posts, and one through the two postsand included upper chord-stick, serving to hold these parts together.The upper packingblock, G, is notched on its under side and fits on theupper corners of the lower sticks of the top chord and into a notch madein the upper stick of the said chord. Bolts pass through thecontact-surfaces ot'said sticks and packing- The main braces F (shown inFig. 1) are made of a square piece of timber, to which is secured atriangular covering-piece, f, made by sawing a square piece of wooddiagonally i'rom corner to corner. This triangular covering-piece formsthe exposed or upper surface of brace and acts as a water-shed. Timbersof a similar construction can also be used on other parts of thebridge-as, for instance, the lower tiers of upper and lower chords andfloor-beams and for track-sills.

Referring to Fig. 2, it will be seen that the end posts rest directlyupon the abutments or piers, and tha the bottom chords and lowercross-timbers are secured to said posts above the lower ends of saidposts. This necessarily causes the chords and cross-timbers to bearranged above the abutment, so that they will not lie upon the same andbe exposed to the decaying influence of moisture.

In Figs. 3, 4, and 5 I have illustrated a wagonbridge strain-beam truss,in which the bottom chords are each composed of pairs of upper and lowersticks secured to posts that rest upon the abutments and hold the chordsabove the latter.

In all forms of bridging, where there is danger of earth coming incontact with and of imparting moisture to the ends of thechordsticks andfeet of end posts, I would attach to the end of each chord-stick a smallcast-iron block or bar, against which a breastwork of planks should bemade to rest, separating the earth from the timbers and moisture fromthe ends of the chords and posts, as shown in Figs. 3 and 4.

I am aware of Letters Patent No. 33,629, dated November 5, 1861, and donot claim what is therein shown; but,

Having thus described my invention, what I claim is- 1. A wooden-trussbridge having its various chords, vertical posts, braces, andcross-timbers arranged with inclined water and fire shedding surfaces,the timbers where they cross each other in contact being joined togetherby the lower timbers fitting into a notch in the lower corners of theupper timbers, sub stantially as described.

2. A wooden bridge having its component timbers arranged so as topresent angular snrfaces the apices of which approximately coincide withhorizontal and vertical lines, substantially as described.

3. The combination of double-tiered upper and lower chords andtransverse floor-beams locked to each other and to packing-sticks and toand about the posts by bolts and notches, substantially as described.

In testimony whereof I have hereunto set my hand and seal in thepresence of two subscribing witnesses.

WILLIAM JENNINGS HOLMAN.

\Vitnesscs:

GEORGE L. BITTINc-ER,

D. A. WoRDwonrn.

